Wrench



Patented Dec. 2, 1952 UNITED OFFICE 2,620,051 WRENCH Reuben A. *Kaplan, Owatonna; Minn.

iApplication'Julyz i, 1948, Serial No. 40,445

? 2*.Claims. (Cl. 19.2-43.1)

This inventionrelates to-ratchet-wrenches, and particularly to a wrench-of'the type comprising a head having a cylindrical barreland a-core rotatable therein which may be utilized for turning wrench sockets orother driven members.

An object of the invention is to provide a wrench comprising improved -mechanism for reversing the direction of the core so that the driven member may be rotated in 'either direction.

A further object of the invention is to provide a wrench which is capable of transmitting great torque without breakage of or damage to the parts thereof.

A further object ofthe'invention' is to provide awrench which is simple in construction, easily manufactured, and efiicient and *durableinuse.

Furtherobjects and advantages of the invention will be apparent from the vfollowing description, in which:

Fig. 1 is'a view in longitudinal elevation'of a wrench embodying the invention.

.Fig. 2 is a'plan-view of-the-head of the wrench. Fig. 3 is, an enlarged sectional View of the same, taken on the line 3-3 of Fig. 1.

Fig. 4 is a sectional View taken on the line 44 of Fig. 3.

Fig. 5 is a fragmentary sectional view taken on the line 5-5 of Fig. 3.

It is to be understood that the invention is not limited in its application to the details of construction and arrangement of parts illustrated in the accompanying drawings, since the invention is capable of other embodiments and of being practiced or carried out in various ways. Also it is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation.

The wrench shown in the drawing comprises a handle I0 formed with a head which includes a generally cylindrical barrel I'2 having therein a rotatable core, described hereinafter. At one end of the barrel I2 an apertured disk I4 is secured as by welding to the inner surface or bore of the barrel. The inner surface of the barrel is provided at its midsection with ratchet teeth I6 having truncated crests as indicated in Fig. 3. At the ends of the teeth the inner surface of the barrel is counterbored to cylindrical form having a diameter at least as great as the root diameter of the teeth I6, to receive the disk I4 and a retaining plate to be described.

The rotatable core of the head comprises a block I8 of generally cylindrical form shaped to rotate with sufficient clearance within the cylinder defined by the flatted crests of teeth I6. Formed integral with the block I8 is a stud I9 of "2 rectangular crosslsection designedto engage and rotate awrench socket or other driven member, as-described hereinafter. At onesidegthe block I8 is cut away to form a wedge-shaped boss 20 having a'truncated-tip 22 the outer surface of which lies within the cylinder defined by *the crestsof teeth I8. At the base of the-boss 28 are formed opposite cylindrical sockets into which fit the cylindrical butts 24, 25 of two pawls '26, '21, the free ends or blades of which are designed to engage teeth I6. As indicated in Fig. 4, thepa-wls are-of substantially the same widthas teeth I6, and their upper-ends or butts are enlarged togive ample bearing area in their .respective sockets.

Pivoted-tothe boss 20 by a pin"'28-is aswitch bracket 30. The bracket 30 "has two opposite arms which terminate .in :rounded ends 32, 133 which act as cam followers aseXplained hereinafter. The arms are also provided with ears :3'4, 35 which-act, upon the bracketbeing rockedto one or the other of its two-extreme positions, 1 to force one of the pawls 26, 21 into :proximity :with one face'of boss ZU-and outof the-path cfthe: teeth I6, while permitting' the other pawl to be moved by a compression spring 36 outwardly to a position wherein it will engage the teeth I6, as best shown in Fig. 3. Each of the springs 36 is set in a small socket formed in boss 20 as shown in Fig. 5..

In order to actuate the bracket 30 and thus reverse the direction of rotation of the block I8 and stud I9, a knurled reversing knob 38 is rotatably mounted at the side of barrel I2 opposite to the stud I9. The knob 38 is formed with an annular shoulder 48 which fits rotatably against an annular flange 42 formed on block I8. The knob 38 is also formed with an inner extension 44 which fits rotatably within a bore formed in block I8. The extension 44 is of generally cylindrical form, but is machined to form two fiat cam faces 46, 41 designed to engage one or the other of the ends 32, 33 of bracket 38 as the knob 38 is rotated.

The knob 38 is held in place by a stud 48, the shank of which extends through an axial bore formed in the knob. The stud 48 has a threaded end 49 of reduced diameter which engages a threaded bore in block I8, and an enlarged head 50 which is rotatable in a counterbore in knob 38 and which is formed with a hexagonal socket to receive a small wrench 52 as indicated in dotted lines in Fig. 2. In assembling the parts just described, the stud 48 is turned inwardly until its shank firmly seats in the block I8, which leaves the knob 38 free to rotate.

In order to retain the rotary core in the barrel of the wrench, a retaining plate 54 is mounted within the barrel I2 opposite the disk I4 and is retained permanently in place by spinning the metal of the barrel over it as indicated in Fig. 4. The disk 54 is formed with a central aperture of such size as to rotatably embrace the flange Q2 and thus to exclude dirt from the core.

The stud I9 may be of any suitable construction, but as shown comprises a ball 56, urged outwardly in a transverse bore of the stud by a compression spring, not shown, to enable it to releasably retain a wrench socket 60 which is formed with a recess to receive the stud, in known manner.

With the parts in the positions indicated in Fig. 3, it will be seen that counterclockwise torque applied by handle in is transmitted through barrel l2 and teeth IE to the pawl 2!25, which is thus put under compression and exerts a force in the counterclockwise direction upon the core I8 at such distance from the center of the core that a high torque may be transmitted to the stud IS without unduly straining the parts. By reason of the construction above described, the wrench may be subjected to heavy duty without failure of the parts.

Although the invention has been described with reference to a particular embodiment thereof, it may be embodied in other forms within the skill of artisans in this art, and is therefore not limited except in accordance with the terms of the following claims.

I claim:

1. A Wrench comprising a head having a bore extending therethrough and provided with teeth defining a cylinder, a core rotatable in said cylinder and having a generally cylindrical portion recessed throughout its length to form a radially tapering boss, a pair of oppositely disposed pawls each having a cylindrical end rotatable in a socket in said core and its other end movable into engaging and non-engaging positions relative to said teeth, springs urging the pawls into engagement with the teeth, and a reversing mechanism comprising a cam member coaxially rotatable in said portion and having a cam surface including a circular portion and two plane surfaces intersecting each other at an obtuse angle, a bracket pivoted to said boss and having two arms each positioned to selectively contact one of said plane surfaces or said circular portion, and elements on each of said arms for drawing one of said pawls out of engagement with the teeth when the corresponding arm is in contact with one of said plane surfaces.

2. Wrench mechanism comprising a driving head having a bore extending therethrough and provided with internally extending teeth defining a cylinder, a core rotatable in said cylinder and having a generally cylindrical p rtion cut away to form a radially extending boss, 2. pair of spring pressed pawls having their inner ends pivotally mounted in sockets at opposite sides of said boss and thin outer ends movable into and out of engagement with said teeth to form therewith a ratchet, and a reversing mechanism comprising a cam rotatable in said portion and having a cam surface including a circular portion and two intersecting plane surfaces, a bracket pivoted to said boss to be moved by said cam and having two arms each positioned to selectively contact one of said plane surfaces or said circular portion, and elements on each of said arms for drawing one of said pawls out of engagement with the teeth upon contact of the corresponding arm with one of said plane surfaces.

REUBEN A. KAPLAN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Kress Sept. 10, 1946 

